Contour facing attachment



May 9, 1961 E. H. JOHNSON El'AL CONTOUR FACING ATTACHMENT Filed June 9, 1955 4 Sheets-Sheet 1 ,FIG.I

INVENTORS. V ERNEST H. JOHNSON WALTER A. EHRLIGH BY DWARD A. ZUKOWSKI ATT RNEY y 1961 E. H. JOHNSON ETAL 2,983,174

CONTOUR FACING ATTACHMENT 4 Sheets-Sheet 2 Filed June 9, 1955 mm m0 3O 5 an I 0] W0 PM INVENTORS. ERNEST H. JOHNSON WALTER A. EHRLICH BY (%RD A. ZUKOWSKI ATT NEY FIG.2

May 9, 1961 E. H. JOHNSON ETAL 2,983,174

CONTOUR FACING ATTACHMENT Filed June 9, 1955 4 Sheets-Sheet 5 1 M H I;

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ERNEST H. JOHNSON ZUKOWSKI WALTER A. EHRLICH 44* BY @0 A %r%RNEY United States Patent CONTOUR FACING ATTACHMENT Ernest H. Johnson and Walter A. Ehrlich, Bridgeport, and Edward A. Zukowski, Devon, Conn., assignors to The Bullard Company, a corporation of Connecticut Filed June 9,1955, Ser. No. 514,244

4 Claims. (Cl. 82-2) The present invention relates to machine tools and particularly to' a new and improved contour facing attachment for a machine tool. In the fabrication ofmany devices, among which include crank cases and pump housings, it often becomes necessary to face-turn a surface that follows a contour other than a circle.

The principal object of the present invention is to provide an attachment for a lathe which will not only cause a tool to follow an irregular contour during a facing operation, but will simultaneously effect a step-bystep feeding movement of the tool.

Other objects of the invention include the provision of a contour facing attachment which will cooperate with a tool-supporting head of a lathe such that during the initial feeding of the attachment toward the work, the attachment will register, and remain in definite phase relation with the rotatable work-supporting spindle, accurately following an irregular contour during a facing operation; the provision of such an attachment in which a secondary motion is imparted to the tool to provide a step-by-step feeding action of the tool to progressively face the work along an irregular contour; and the provision of an attachment for a lathe inwhich the tool support is adapted radially to be reciprocated in accord-' ance with a predetermined pattern by the rotation of the work-supporting spindle, while at the same time, the tool support is adapted to be progressively fed into the work.

The above, other objects and novel features of the invention'will become apparent from the following specification and the accompanying drawings, in which:

Fig. 1 is a partial sectional elevational view of a vertical lathe to which the attachment forming the present invention is applied;

Fig. 2 is a sectional elevational view taken substantially along line 2-2 of Fig. 1;

Fig. 3 is a partial sectional elevational view of the attachment to which the principles of the invention have described inrelation to a multiple-spindle vertical lathe of the type shown in Patents 2,423,223 in the name of E. P. Bullard III et al., and 1,382,339 in the name-of E. P. Bullard.

Referring to the drawings, and particularly to Fig. 1,

the attachment forming the subject of this invention is shown as applied to a lathe including a base 100, a column 101 fixed to the base, and a platform 102 mounted on top of the column 101. A power input bracket 103 mounted on top of platform 102 is adapted to drive a shaft 104 to' which a gear 105 is fixed. The gear 105 mesheswith a gear 106 which in turn meshes with a gear 107. The gear 107 is fixed to a shaft 108 that also supports a worm 109 in mesh mm a worm wheel 110 that is fixed to a shaft 111. A worm 112 in mesh with a Patented May 9, 1961 worm wheel 113 fixed to a drum cam 114 is adapted to be clutched to shaft 111 by the shifting of a clutch 115. Accordingly, drum cam 114 can be rotated at a constant traverse speed through the gearing and clutch 115 just described.

The shaft 108 also has fixed to it a gear 116 that meshes with a gear 117 keyed to a shaft 118. The shaft 118 extends downwardly through the column 101 and has keyed to its bottom end a gear 119 that meshes with a gear 120 fixed to a spindle 121 that supports a table 122 on which may be mounted a work-supporting fixture 63.

A worm 123 on shaft 118 may mesh witha worm wheel 124 keyed to a shaft 125, to the outer end of which a gear 126 is fixed. The gear 126 meshes with a gear 127 that is journaled on an axis coincident with the axis on which worm 112 is mounted. The gear 127 is adapted to be clutched to, or released from driving engagement with worm 112 by the action of a clutch 128.

From the foregoing it is evident that the cam drum may be rotated at a relatively rapid traverse rate through clutch 115, and at a feed rate through clutch 128, which latter rate may be changed by changing gears 116, 117,

126 and 127. The cam drum 114- may include a cam path 129 in which a roll may ride that is connected to the upper end of a rod 10.

The rod 10 extends downwardly into an elongated hollow clamp 11 to which it is effectively clamped by screws 12. Referring to Fig. 4, a rack 13 is bolted to the lower end of the clamp member 11, and the upper portion on the one side of said clamp member 11 is provided with away 14 that is adapted to cooperate with a mating guide member 15 that is pinned, and rigidly secured to the body 16 of the head H. The cooperation between the way 14 and the guide 15 is such that relative sliding motion is adapted to be provided between the clamp member 11 and the body 16. A connection is provided between the clamp member 11 and the body member 16 for causing the two to move downwardly and upwardly in unison and comprises the type of connection shown, described and claimed in Patent 1,382,339, to which patent reference is made for specific features not specifically shown herein. The rack 13 meshes with a pinion 17 integral with a stub shaft 17 that is jourualed within the body member 16.. A locking pin 18 includes a passage 130 having cam surfaces 131, 132 and 133 therein. A spring 134 urges the pin 18 leftwardly (Fig; 2) so that a spring pressed detent 135 fits up into a notch 136 in the bottom surface of pin 18.

A pivoted finger 137 cooperates with the detent 135 and also cooperates with an abutment 138 that may be adjustably located relatively to the saddle or body 16. The construction and arrangement of the parts are such that as rod 10 moves downwardly, the cam surface 133' on pin 18 engages a cam surface 139 on the rack 13 and through the detent 135 looks the rack 13 and pinion 17 together so that the entire head -16 with the attachment moves downwardly. When the finger 137 engages abutment 138, it withdraws detent 135 fromnotch 136 so that pin 18is forcedleftwardly'into a notch 140, thereby opposite that to which the pinion 17 is fixed, and the pinion 19 meshes with an identical pinion (not shown) that is fixed to a shaft 20 journaled within a housing member 21. The housing member 21 is flangedand bolted'by bolts 22 (Fig. 3) to the body member 16.-

From the foregoing it is evident that downward move 40 at all times.

ment of the rod by the action of the feed cam 134 of the machine tool, causes the entire assemblage including the clamp member 11, the body 16 and the housing 21, to move downwardly in unison until the lock pin 18 is released. Release of the pin 18 causes the body member 16 and housing 21 to stop, while the rack 13 together with the clamp member 11 and the rod 10 continue to move downwardly. Accordingly, the pinions 17,

19, the undisclosed mating pinion that meshes with the pinion 19, and the shaft 20, are caused to rotate for a purpose to be described later.

The housing member 21 isvprovided with a shaft 25 that is connected by an element 26 to a vertically extending shaft 27. The shaft 27 extends upwardly through cam drum 114 and has a gear 141 fixed to its upper end which meshes with a gear 142 that is integral with gear 117. The lower end of the shaft 25 has fixed to it a spur gear 28- that meshes with an internal ring gear 2 9 fixed to a cylindrical support 30. The support 30 is journaledon a tubular member 31 that is bolted to the housing 21 by screws 32 (Fig. 3). A cam plate 33 (here shown in two parts) is fixed to the lower end of the support 30 and includes a cam path 34 therein.

A housing member 35 is bolted to the lower end of the tubular supporting member 31 by bolts 36, and a bottom cover plate 37 is bolted to the housing member 35 by bolts 38. The housing member 35 and the bottom plate 37 provide a chamber 39 (Fig. 3) within which a toolsupporting member 40 is mounted for sliding movement. The one end of the tool support 40 has fixed to it a tool bit 41 that extends downwardly through an opening 42 within the bottom plate 37. The center portion of the sliding tool support 40 is provided with a recess 43 (Pig. 4) that is straddled by a rack 44 (Fig. 3) fixed to the tool support 40 by bolts 45 and 46. The rack 44 is adapted to mesh with a pinion 47 journaled between side walls 48 and 49 of a recessed plate member 51 that is slidingly mounted on the top of the tool support 40'. The diameter of the pinion 47 is such that it extends downwardly into the recess 43 within the slidable member 40; and, the width of the rack 44 is only one-half that of the gear 47 for a purpose to be described later. The one end of the slidable member 51 is provided with a trunnion bearing 52 that supports a cam roll 53 adapted to ride within the cam groove 34 formed in the cam plate 33. The cam groove 34 may be of any contour and, in the present instance, it comprises an elliptical cam path. Accordingly, as the cylindrical support 30 is rotated by rotation of the internal ring gear 29, the non-rotatable member 51 is caused to reciprocate. The reciprocation of the member 51 is transferred to the tool holder 40 through the pinion 47, rack44, 'a rack 54 and. a roll 55 mounted on a pin '56 that extends across the recess that is formed by sidewalls 48'and 49 of the slidable member 51. The construction and arrangement of the parts are such that roll 55 maintains rack 54 in mesh with pinion 47 so that a rigid connection exists between plate 51 and member Accordingly, as the cylindrical support 30,rotates, the tool bit 41 reciprocates radially of the rotatable work piece W so that if the latter and the member 30 are maintained in phase relation, the tool bit 41' will follow the desired elliptical contour of the work piece W as the latter is rotated.

In order to face the work W by a progressive feeding action, it is necessary to progressively move the tool bit 41 into the work. This is accomplished by the cooperation of an additional rack 57 that is slidingly mounted within the housing 21 and to which rack 54 is pivotally connected by a pin 58. The rack 57 meshes with a pinion 59 that is fixed to the shaft 20 previously described. Accordingly, as the rack 57 moves downwardly, it causes the downward movement of the rack 54, thereby rotating the pinion 47 in a counter-clockwise direction and, consequently, feeding the tool support 44 rightwardly as it is continuously reciprocatedunder the influence of the cam path 34. The lower end of rack 54 is adapted to pass downwardly through recess 43 along side of rack 44.

In order to maintain the proper phase relation between the rotatable member 30 and the rotatable work piece W, accurate registration between the two must be provided. In the present embodiment, registration lugs 60 and 61 are attached to a fixture 63 that holds the work W. They include means 64 and 65 that cooperate with depending registering means 66 and 67 mounted within housing elements .68 and 69 that are fixed to the rotatable support 30. The members 66 and 67 extend upwardly into cylindrical openings within the members 68 and 69, and springs 68 and 69' are provided within said openings for resiliently urging the registering means 66 and 67 downwardly.

In order to take up anyback-lash between the rack 57, the gear 59, the gears 19, 17, and the rack 13, a spring 70 is mounted between the top of the housing 21 and a cap 71 that is fixed to the top of the rack 57. V

In operation, as the rod 10 is moved downwardly by the cam 114 of the feedworks, the entire assembly including the rack 13, the body member 16, the housing 21 and the registering members 66 and 67 move downwardly in unison toward the registeringmeans 60 and 61 on the fixture 63. At the same time, the rotation of shaft 27 rotates the ring .gear 29 and the support 30including the registering means 66 and'67 at a rate diiferent from the rate of rotation of the work-supporting fixture 63. This is necessary in order. to eliminate shock when the registering means 66 and 67 engage the registering means 64 and 65 on the fixture 63. The adjustable releasing means 138 that controls the release of the locking pin 18 is set such that the locking pin 18. is released after cooperation is effected between the members 66, 67, and 60, 61. When registration between these members is effected, the rotation of the fixture 63 which is greater than the rotation of the support 30, then takes over and acts as the drive for the support 30. In order to accomplish this, an over-running clutch (not shown) is employed in the drive for the shaft 27.

Upon release of the locking pin 18, the housing 21 and body member 16 cease to descend, while the rack 13 continues to move downwardly. Continued downward movement of the rack 13 rotates the pinions 17 and 19 and 59, thereby causing the rack member 57 to move downwardly together with the pivotally mounted rack 54. This action rotates the pinion 47 in a counter-clockwise direction thereby moving the tool support 40 (Fig. 3) rightwardly, progressively feeding the tool bit 41 into the work while, at the same time, the tool support 44 is reciprocated in a proper manner to cooperate with the elliptical surface to be face-turned on the work piece W. V 7

Although the various features of the new and improved contour facing attachment have been shown and described in detail to fully disclose one embodiment of the invention, it will be evident that numerous changes may be made in such details, and certain feat-ures may be used without others, without departing fromthe principles of the invention.

What is claimed is: V

1. In a machine tool, a base; a column attached to said base; a work-supporting table mounted in said base for rotation about a vertical axis; a tool head mounted on said column; means for moving said tool head towardand from said work support; a freely rotatable cam mounted said tool head for rotation about an axis co-extensive with the axis of rotation of said worksupponting table; means on said cam adapted to cooperate with means on said work-supporting table for preventing relative rotation between said cam and table when said tool head has been moved a predetermined distance toward said table; a reciprocable member within said to'ol head; follower means within said tool head for causing said cam to impart a movement to said reciprocable member transversely of the axis of rotation of said work support; a tool support connected to said reciprocable member for reciprocation therewith; and means responsive to the continued movement of said tool head moving means for imparting to said tool support a feeding motion relatively to said reciprocable member.

2. In a machine tool, a base; a column attached to said base; a work-supporting table mounted in said base for rotation about a vertical axis; a tool head mounted on said column; means for moving said tool head toward and from said work support; a freely rotatable cam mounted within said tool head for rotation about an axis co-extensive with the axis of rotation of said worksupporting table; registering means between said cam and work-supporting table for preventing relative rotation between said cam and table when said tool head has been moved a predetermined distance toward said table; a reciprdoable member within said tool head; follower means within said tool head for causing said cam to impart a movement to said reciprocable member transversely of the axis of rotation of said work support; a tool support connected to said reciprocable member for reciprocation therewith; and means responsive to the continued movement of said tool head moving means for imparting to said tool support a 'feeding motion relatively to said reciprocable member.

3. In a machine tool, a base; a colunm attached to said base; a work-supporting table mounted in said base for rotation about a vertical axis; a tool head mounted on said column; means for moving said tool head toward and from said work support; a freely ro'tatable cam mounted within said tool 'head for rotation about an axis co-extensive with the axis of rotation of said work-supporting table; means on said cam adapted to cooperate with means on said work-supporting table for preventing relative rotation between said cam and table when said tool head has been moved a predetermined distance toward said table; a reciprocable member within said tool head; follower means within said tool head for causingsaid cam to impart a movement to said reciprocable member transversely of the axis of rotatio'n of said work support; a tool support connected to said reciprocable member for reciprocation therewith and rack and pinion means responsive to the continued movement of said tool head 6 moving means for imparting to said tool support a feeding motion relatively to said reciprocable member.

4. In a machine tool, a base; a column attached to said base; a work-supporting table mounted in said base for rotation about a vertical axis; a tool head mounted on said column; movement imparting means :for said tool head comprising a rack and pinion adapted to be locked while imparting movement to said tool head; means for releasing said locking means; a freely rotatable cam mounted within said tool head for rotation about an axis co-extensive with the axis of rotation of said worksupporting table; means on said cam adapted to cooperate with means on said work-supporting table for preventing relative rotation between said cam and table when said tool head has been moved :a predetermined distance toward said table; a reciprocable member within said tool head; follower means Within said tool head for causing said cam to impart a movement to said reciprocable member transversely of the axis of rotation of said work support; a tool support connected to said reciprocable member for reciprocation therewith; and means responsive to the releasing of said locking means and the rotation of said pinion means for imparting to said tool support a feeding motion relatively to said reciprocation member.

References Cited in the file of this patent UNITED STATES PATENTS 1,249,642 Lindfors Dec. 11, 1917 1,382,339 Bullard June 21, 1921 1,428,801 Oulton Sept. 12, 1922 1,500,637 Pillar July 8, 1924 1,811,876 Bullard June 30, 1931 1,865,239 Deleeuw June 28, 1932 2,069,296 Woytych Feb. 2, 1937 2,367,555 Arney Jan. 16, 1945 2,404,433 Christman July 23, 1946 2,487,243 HoErvath Nov. 8, 1949 2,487,994 Trevena Nov. 15, 1949 2,540,186 Bullard Feb. 6, 1951 2,777,351 Johnson Jan. 15, 1957 

